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INTRODUCTION Late gadolinium enhancement (LGE) cardiac magnetic resonance imaging (MRI) can be used to detect postablation atrial scar (PAAS) but its reproducibility and reliability in clinical scans across different magnetic flux densities and scar detection methods are unknown. METHODS Patients (n = 45) having undergone two consecutive MRIs (3 months apart) on 3T and 1.5T scanners were studied. We compared PAAS detection reproducibility using four methods of thresholding: simple thresholding, Otsu thresholding, 3.3 standard deviations (SD) above blood pool (BP) mean intensity, and image intensity ratio (IIR). We performed a texture study by dividing the left atrial wall intensity histogram into deciles and evaluated the correlation of the same decile of the two scans as well as to a randomized distribution of intensities, quantified using Dice Similarity Coefficient (DSC). RESULTS The choice of scanner did not significantly affect the reproducibility. The scar detection performed by Otsu thresholding (DSC of 71.26 ± 8.34) resulted in a better correlation of the two scans compared with the methods of 3.3 SD above BP mean intensity (DSC of 57.78 ± 21.2, p

Frying oils are prone to quality deterioration; because of the high surface area, lipid molecules can interact with air, moisture, and oxidative reagents that promote various reactions. However, the search for effective ingredients for stabilizing frying oil has been slow, given the complexity of the frying processes and lack of effective tools to accurately predict the performance of emerging ingredients. On the other hand, demand for label-friendly food ingredients has increased. This study aimed to develop a rapid method mimicking real frying conditions to allow the screening of a large number of treatments with improved throughput, while evaluating their effectiveness in stabilizing frying oils. The design utilizes multi-well heating blocks of conventional OSI. Repeated frying was conducted using miniature baskets, and validations were conducted to examine the accuracy of the relative efficacy of individual treatments. Utilizing this method as a tool, natural plant extracts, standard antioxidants, and their combinations were evaluated and compared in frying palm oil, which demonstrated that the combination of tocopherols, rosemary extract, and oil-soluble green tea extract was effective for the stabilization of frying oil.

Purpose To develop an estimate of pulmonary vascular resistance (PVR) using blood flow measurements from 3D velocity-encoded phase contract magnetic resonance imaging (here termed 4D MRI). Materials and Methods In all, 17 patients with pulmonary hypertension (PH) and five controls underwent right heart catheterization (RHC), 4D and 2D Cine MRI (1.5T) within 24 hours. MRI was used to compute maximum spatial peak systolic vorticity in the main pulmonary artery (MPA) and right pulmonary artery (RPA), cardiac output, and relative area change in the MPA. These parameters were combined in a four-parameter multivariate linear regression model to arrive at an estimate of PVR. Agreement between model predicted and measured PVR was also evaluated using Bland–Altman plots. Finally, model accuracy was tested by randomly withholding a patient from regression analysis and using them to validate the multivariate equation. Results A decrease in vorticity in the MPA and RPA were correlated with an increase in PVR (MPA: R2 = 0.54, P < 0.05; RPA: R2 = 0.75, P < 0.05). Expanding on this finding, we identified a multivariate regression equation that accurately estimates PVR (R2 = 0.94, P < 0.05) across severe PH and normotensive populations. Bland–Altman plots showed 95% of the differences between predicted and measured PVR to lie within 1.49 Wood units. Model accuracy testing revealed a prediction error of ∼20%. Conclusion A multivariate model that includes MPA relative area change and flow characteristics, measured using 4D and 2D Cine MRI, offers a promising technique for noninvasively estimating PVR in PH patients. J. MAGN. RESON. IMAGING 2016;44:914–922.

Studies of predator–prey demographic responses and the physical drivers of such relationships are rare, yet essential for predicting future changes in the structure and dynamics of marine ecosystems. Here, we hypothesize that predator–prey relationships vary spatially in association with underlying physical ocean conditions, leading to observable changes in demographic rates, such as reproduction. To test this hypothesis, we quantified spatio-temporal variability in hydrographic conditions, krill, and forage fish to model predator (seabird) demographic responses over 18 years (1990–2007). We used principal component analysis and spatial correlation maps to assess coherence among ocean conditions, krill, and forage fish, and generalized additive models to quantify interannual variability in seabird breeding success relative to prey abundance. The first principal component of four hydrographic measurements yielded an index that partitioned “warm/weak upwelling” and “cool/strong upwelling” years. Partitioning of krill and forage fish time series among shelf and oceanic regions yielded spatially explicit indicators of prey availability. Krill abundance within the oceanic region was remarkably consistent between years, whereas krill over the shelf showed marked interannual fluctuations in relation to ocean conditions. Anchovy abundance varied on the shelf, and was greater in years of strong stratification, weak upwelling and warmer temperatures. Spatio-temporal variability of juvenile forage fish co-varied strongly with each other and with krill, but was weakly correlated with hydrographic conditions. Demographic responses between seabirds and prey availability revealed spatially variable associations indicative of the dynamic nature of “predator–habitat” relationships. Quantification of spatially explicit demographic responses, and their variability through time, demonstrate the possibility of delineating specific critical areas where the implementation of protective measures could maintain functions and productivity of central place foraging predators.

Objectives: The Global Emergency Medicine Literature Review (GEMLR) conducts an annual search of published and unpublished articles relevant to global emergency medicine (EM) to identify, review, and disseminate the most important research in this field to a wide audience of academics and practitioners. Methods: This year, 7,924 articles written in seven languages were identified by our search. These articles were divided up among 20 reviewers for initial screening based on their relevance to the field of global EM. An additional two reviewers searched the grey literature. A total of 206 articles were deemed appropriate by at least one reviewer and approved by their editor for formal scoring of their overall quality and importance. Results: Of the 206 articles that met our predetermined inclusion criteria, 24 articles received scores of 17 or higher and were selected for formal summary and critique. Interrater reliability for our scoring system was good with an interclass correlation coefficient of 0.628 (95% confidence interval = 0.51 to 0.72). Conclusions: Compared to previous reviews, there was a significant increase in the number of articles that were devoted to emergency care in resource-limited settings, with fewer articles related to disaster and humanitarian response. The majority of articles that met our selection criteria were reviews that examined the efficacy of particular treatment regimens for diseases that are primarily seen in low- and middle-income countries.

The International Emergency Medicine (IEM) Literature Review aims to highlight and disseminate high-quality global EM research in the fields of EM development, disaster and humanitarian response, and emergency care in resource-limited settings. For this review, we conducted a Medline search for articles published between January 1 and December 31, 2010, using a set of international and EM search terms and a manual search of journals that have produced large numbers of IEM articles for past reviews. This search produced 6,936 articles, which were divided among 20 reviewers who screened them using established inclusion and exclusion criteria to select articles relevant to the field of IEM. Two-hundred articles were selected by at least one reviewer and approved by an editor for scoring. Two independent reviewers using a standardized and predetermined set of criteria then scored each of the 200 articles. The 27 top-scoring articles were chosen for full review. The articles this year trended toward evidence-based research for treatment and care options in resource-limited settings, with an emphasis on childhood illness and obstetric care. These articles represent examples of high-quality inter- national emergency research that is currently ongoing in high-, middle-, and low-income countries alike. This article is not intended to serve as a systematic review or clinical guideline but is instead meant to be a selection of current high-quality IEM literature, with the hope that it will foster further growth in the field, highlight evidence-based practice, and encourage discourse. ACADEMIC EMERGENCY MEDICINE 2011; 18:872-879 a 2011 by the Society for Academic Emergency Medicine

Dendrochronology (tree-ring analysis) techniques were applied to develop chronologies from the annual growth-increment widths of red snapper (Lutjanus campechanus) and gray snapper (Lutjanus griseus) otoliths sampled from the northern Gulf of Mexico, USA. Growth increment widths showed considerable synchrony within and across species, indicating that some component of environmental variability influenced growth. The final, exactly dated red snapper chronology continuously spanned 1975 through 2003, while the gray snapper chronology continuously spanned 1975 through 2006. To determine baseline climategrowth relationships, chronologies were compared to monthly averages of sea surface temperatures, U winds (west to east), V winds (south to north), and Mississippi River discharge. The gray snapper chronology significantly (P < 0.01) correlated with winds and temperature in March and April, while the red snapper chronology correlated with winds in March. Principal components regression including springtime winds and temperature accounted for 28 and 52% of the variance in the red and gray snapper chronologies, respectively. These results indicate that snapper growth was favored by warm sea surface temperatures and onshore winds from the southeast to the northwest in March and April. Overall, this study provides preliminary, baseline information regarding the association between climate and growth for these commercially important snapper species.

Analysis of monthly coastal upwelling intensities revealed two seasonal and biologically relevant upwelling ‘modes’in the California Current Ecosystem (CCE). The first mode reflected upwelling during the summer months and wascharacterized by low-frequency (multidecadal) processes, including significant (Po0.01) linear trends at somelatitudes. In contrast, the second mode reflected wintertime upwelling and was defined by higher-frequencyvariability associated with the North Pacific High and El Nin˜o Southern Oscillation events. These modes werecompared with multidecadal time series of splitnose rockfish (Sebastes diploproa) otolith growth, yelloweye rockfish(S. ruberrimus) otolith growth, Chinook salmon (Oncorhynchustshawytscha) scale growth, and indices of Cassin’s auklet(Ptychoramphus aleuticus) and common murre (Uria aalge) reproduction in the central-northern CCE. In redundancyand correlation analyses, salmon growth and Cassin’s auklet fledgling success associated with the summer upwellingmode while all other time series associated with the winter upwelling mode, indicating that CCE biology wasdifferentially sensitive to these seasonal upwelling patterns. Thus, upwelling occurred in unrelated seasonal modeswith contrasting trends, atmospheric forcing mechanisms, and impacts on the biology of the CCE, underscoring theimportance of seasonality when evaluating ecosystem response to climate variability and change.

ACADEMIC EMERGENCY MEDICINE 2011; 18:255–260 © 2011 by the Society for Academic Emergency Medicine Abstract Objectives: There is a growing awareness of the effects of patient death on physician well-being, and the importance of cultural and educational changes to improve coping mechanisms. The objective of this study was to explore both the effects of patient death on academic emergency physicians (EPs) and the coping mechanisms they use to deal with these events. Methods: Faculty at a convenience sample of four emergency medicine (EM) residency programs were questioned about their responses to patient death in a 15-question on-line survey. Descriptive analysis of the data was performed. Independent variables were analyzed for differences in complaints of physical symptoms or consideration of important life changes after patient death. Results: Of 207 EPs surveyed, 145 (70%) responded. Patient death was experienced frequently, with 95 (66%) witnessing a death at least every month. No training on coping with patient death had occurred for 35 (24%); 93 (64%) had less than 6 hours of training. The most common coping mechanisms included talking with colleagues (113; 78%) or friends and family (100; 69%), as well as simply continuing to work (89; 61%). Postdeath debriefing occurred rarely or never for 93 (64%) of respondents. Most EPs had experienced physical responses to patient death, the most common being insomnia (54; 37%) and fatigue (21; 14%). Common emotional responses included sadness (112; 70%) and disappointment (55; 38%). No significant differences in response rates for physical symptoms or consideration of life changes were found for any of the variables. Conclusions: Patient death was reported to lead to both physical and emotional symptoms in academic EPs. Postdeath debriefing appears to happen infrequently in teaching settings, and most respondents reported that they themselves received limited training in coping with patient death. Further study is needed to both identify coping mechanisms that are feasible and effective in emergency department settings and develop teaching strategies to incorporate this information into EM residency training.

There is a large body of research that shows children from non-intact homes show higher rates of juvenile delinquency than children from intact homes, partially due to weaker parental control and supervision in non-intact homes. What has not been adequately addressed in the research is the influence of changes in family structure among individual adolescents over time on delinquent offending. Using the first and third waves of the National Youth Study, we assess the effect of family structure changes on changes in delinquent offending between waves through the intermediate process of changes in family time and parental attachment. Although prior research has documented adolescents in broken homes are more delinquent than youth in intact homes, the process of family dissolution is not associated with concurrent increases in offending. In contrast, family formation through marriage or cohabitation is associated with simultaneous increases in offending. Changes in family time and parental attachment account for a portion of the family formation effect on delinquency, and prior parental attachment and juvenile offending significantly condition the effect of family formation on offending.

The taxonomy, distribution, life-history and host plant relationships of the cerambycid Oberea erythrocephala (Schrank), an oliphagous, univoltine stem- and root-miner of Euphorbia spp. are discussed. The results of feeding and oviposition tests with 43 plant species in 20 families, and of larval transfer tests with 31 plant species are presented, and show that O. erythrocephala is restricted to certain species of the genus Euphorbia, not including the ornamental species E. pulcherrima and E. milii. In Europe the beetle is widely distributed and locally quite destructive. It accepts the target weed, Canadian leafy spurge, and develops normally on it and therefore should be relatively easy to establish in the field. The release of O. erythrocephala in Canada is recommended. Zusammenfassung Studien uber Oberea erythrocephala (Schrank) als moglichem Mittel zur biologischen Bekampfung von Euphorbia spp. in Kanada Es werden die Taxonomie, Verbreitung und Lebensweise des Bockkafers Oberea erythrocephala, eines oligophagen, univoltinen Stamm- und Wurzelminierers bei Wolfsmilch, Euphorbia spp. in Kanada erortert. Die Ergebnisse von Futterungs- und Eiablage-Versuchen an 43 Pflanzenarten aus 20 Familien sowie von Larven-Obertragungen auf 31 Pflanzenarten zeigen, das die Existenz von O. erythrocephala auf bestimmte Arten der Gattung Euphorbia, z. B. nicht auf E. pulcherrima und E. milii, beschrankt ist. In Europa hat der Kafer weite Verbreitung. Er entwickelt sich auch in der kanadischen Wolfsmilch und konnte daher in Kanada relativ schnell auf den Feldern Verbreitung finden. Seine Freilassung in Kanada zur biologischen Unkrautvernichtung wird daher empfohlen.

Euzophera cinerosella (Zell.) is a destructive pyralid moth on Artemisa absinthium L. in Europe and appears to be monophagous in its native range. In laboratory feeding tests, adults were obtained when larvae fed on several important browse species of Artemisia as well as other species of Composites. The host range of E. cinerosella is too broad for it to be considered for release in the biocontrol of A. absinthium in Canada. Zusammenfassung Zur Eignung von Euzophera cinerosella (Zell.) (Lep., Pyralidae) als biologisches Mittel der Bekampfung des Unkrauts Artemisia absinthium L. (Compositae) in Kanada Euzophera cinerosella (Zell.) ist eine Pyralide, die innerhalb ihres naturlichen Verbreitungsgebiets anscheinend monophag auf Artemisia absinthium lebt und in verschiedenen Gebieten Europas grose Schaden verursacht. Labortests mit frisch geschlupften Larven haben gezeigt, das sich E. cinerosella auser an der europaischen Artemisia vulgaris auch an einer Anzahl okologisch bedeutender nordamerikanischer Artemisia-Arten, sowie an einigen weiteren Compositen bis zum Falter entwickeln kann. Besonders im Hinblick auf eine eventuelle Gefahrdung nordamerikanischer Artemisia-Arten kann E. cinerosella nicht fur die biologische Bekampfung der eingeschleppten A. absinthium in Kanada berucksichtigt werden.

The binding of lymphocyte function associated antigen (LFA-1) to intercellular adhesion molecule (ICAM-1) is responsible for several types of cellular adhesion. Amino-acid substitution mutants of ICAM-1 have established the importance of several sequences in this protein. We selected the binding region of Glu34 for further study. One published model of domain 1 placed Glu34 near the end of a β-strand. We designed and synthesized three tripeptide derivatives centered on the Glu34 sequence and attached a platform which, through hydrogen bonds, induces a rigid β-strand conformation. Variable temperature NMR methods coupled with NOESY 2D NMR data enabled determination of the solution conformation of these compounds. ©Munksgaard 1996.

Spirituality is a component of many drug and alcohol treatment strategies, and faith-based programming is also common within prison settings. Yet research on religiosity—crime linkages has often relied on general youth or adult samples or has included a short time line for gauging positive effects. Life-course researchers focused on serious delinquents, in turn, have often emphasized other factors associated with long-term crime patterns, such as marital attachment and job stability, or the criminality of the individual's social ties. This study draws on quantitative and qualitative data derived from a long-term follow-up of a sample of serious adolescent male and female offenders to explore the role of spirituality and religious participation as influences on adult patterns of criminal involvement (N= 152). The respondents were first interviewed as adolescents, in 1982, and again as adults in 1995 and 2003. Results of longitudinal analyses that take into account self-report and incarceration histories at both time periods do not reveal a significant association between these indices of religiosity and the likelihood of evidencing a pattern of sustained desistance. Our analysis of indepth life-history interviews conducted with most respondents over these two time periods and 41 additional interviews focused specifically on spirituality and religion are used to explore in more detail the promise and challenges associated with relying on religiosity as a catalyst for sustained behavior change.

Sampson and Laub's age-graded theory of informal social control emphasizes the importance of adult social bonds such as marriage and stable employment in redirecting behavior in a more prosocial direction. Heavy alcohol use has also been shown to influence persistent patterns of offending as well as more episodic offending across the life course. Sampson and Laub's life-course theory emphasizes the negative impact of alcohol use on marital and employment bonds. Although alcohol has indeed been shown to have significant effects on criminal offending, we argue that drug use and the drug culture in which many contemporary offenders are enmeshed have consequences that often complicate desistance processes in ways that alcohol does not. Drug use and its lifestyle concomitants bring together a host of distinctive social dynamics that compromise multiple life domains. The current project investigates the role of drug use on desistance processes relying on a contemporary sample of previously institutionalized youth. We draw on three waves of data from the Ohio life-course study, a project that spans some 21 years. The results support the assertion that drug use exerts unique effects on desistance processes, once levels of alcohol use are taken into account. We investigate possible mechanisms that help to explain the differential impact of drug use on offending and find that social network effects, particularly partner criminality, explain some but not all of the negative impact of drug use on life-course patterns of criminal offending.

A bench scale sequencing batch reactor (SBR) was designed and tested for degradation of 2,4,6-trinitrophenol (TNP) or picric acid-contaminated wastewater or groundwater. Under varying temperatures (25, 15 and 10°C) and influent concentrations (40–200 mg/L TNP) a stable biomass was developed that was consistently capable of degrading the explosive compound to below regulatory drinking water limits (0.057 mg/L). The reactor was initially seeded with a nitroaromatic and nitramine degrading isolate Rhodococcus opacus strain JW01. Kinetic growth modeling was conducted revealing µmax values at 25, 15 and 10°C of 0.14, 0.08 and 0.04 d−1, while the modeled Ks values were 0.68, 1.11 and 1.24 mg/L, respectively. Overall TNP removal efficiency in the SBR was on average > 99.9% over the 2000 hours of operation. Removal of TNP to below drinking water standards, with low residual dissolved carbon and significant release of nitrogen from the parent compound was accomplished. Biotechnol. Bioneg. 2007;97: 1408–1414. © 2007 Wiley Periodicals, Inc.

A literature study was conducted to compare the feasibility of biofilters and biotrickling filters for the treatment of complex odorous waste air containing hydrogen sulfide (H2S), organic reduced sulfur compounds, and chlorinated and nonchlorinated volatile organic compounds (VOCs). About 40 pilot-plant studies and full-scale applications at wastewater treatment plants and other facilities were reviewed. Reactor design and pollutant removal efficiencies were summarized in tables for easy reference and for a perspective on the current state of the art, and to allow comparison between different projects. The survey indicated that both biofilters and biotrickling filters are capable of combining a high H2S and odor removal efficiency with VOC removal. Apart from odor abatement, biological treatment therefore holds promise for reducing the overall toxicity and potential carcinogenicity of VOC-containing odorous waste air from wastewater treatment plants and other facilities. VOC removal efficiencies were in general lower than those of H2S and odor, although concentrations of individual VOC species were relatively low. This indicates that for effective treatment of VOC-containing odorous waste air, the design and operation should emphasize VOC removal as the rate-limiting parameter. © 2005 American Institute of Chemical Engineers Environ Prog, 2005

This study investigated the effect of competition from wheat and below ground herbivory on the growth and reproduction of scentless chamomile, Tripleurospermum perforatum (Merat) Lainz (Asteraceae), a target plant for classical biological control. Field cages, in which scentless chamomile was planted, were established in 1994 near Neuenburg (Rhine Valley, Germany), and two weevil species, Diplapion confluens Kirby and Coryssomerus capucinus (Beck), were released alone (40 adults each) or together in a substitutive design (20 adults each). Wheat was sown alone or in combination with both herbivores as an additional stress factor. To test the cage effect on plant growth, an uncaged control was set up. At the end of the experiment, caged control plants were about 20 cm (18%) higher, and allocated more biomass to shoots and less to roots and seeds than uncaged plants. Competition from wheat reduced the number of shoots per T. perforatum plant from 7.6 to 3.2. As a consequence, the biomass of scentless chamomile plants that competed with wheat was reduced by 39% and reproductive output by 49%, compared with plants that were grown without competition. At the end of the experiment, 70–80% of T. perforatum plants had been attacked by an average of two to three D. confluens and 60–70% of plants by one to two C. capucinus. At these densities that were lower than expected, the two herbivores alone or in combination had no significant effect on any of the plant parameters measured. However, in the presence of wheat, herbivory further reduced the number of shoots per plant. We conclude that control of scentless chamomile using insect biocontrol agents will be more likely to be successful if agent densities are high, and agents are released in habitats where scentless chamomile is competing with other plant species.

A pilot-scale biotrickling filter was installed at the Hyperion Treatment Plant in Los Angeles, California, to study hydrogen sulfide (odor) and volatile organic compound (VOC) removal from headworks waste air. The performance of the reactor was continuously monitored during a 10-month period. At an average empty bed gas residence time of 24 seconds, 10 to 50 ppm of hydrogen sulfide was consistently removed at greater than 98% efficiency, corresponding to an average volumetric elimination capacity of 5.2 g/m3 x h. Concentration profiles over the height of the reactor indicated nearly complete removal in the first section of the reactor, suggesting that elimination capacities up to 30 g/m3 x h could be obtained. The odor reduction (as dilution to threshold) was 98%, which correlated with the efficiency of removal of hydrogen sulfide as the primary pollutant. Volatile organic compounds were present at concentrations up to 225 ppb. Moderate but significant removal of toluene and benzene was observed when the biotrickling filter was operated with pH control to neutralize sulfuric acid production from hydrogen sulfide oxidation. Xylenes and chlorinated VOCs were not removed regardless of experimental conditions in the reactor. The results led to the conclusion that VOC removal is the limiting process in biotrickling filters for the simultaneous removal of hydrogen sulfide and VOCs at publicly owned treatment works.

The objective of this study was to examine both simulator and retrieved total knee replacement polyethylene inserts to confirm, using scanning electron microscopy, whether similar micro-wear patterns to those seen on retrieved inserts were reproduced on simulator specimens. The simulator specimens consisted of samples subjected to sliding and rolling movement (Experiment 1) and to sliding movement only (Experiment 2). Samples from Experiment 1 demonstrated longitudinal patterns in the middle of the wear track and transverse patterns in the anterior and posterior ends, whereas in Experiment 2, only transverse patterns were observed. In the retrieved specimens, both longitudinal and transverse patterns were observed. The results showed that the simulator study reproduced similar patterns of micro-damage on polyethylene, and that the longitudinal micro-wear pattern was related to the rolling movement that is distinctive in knee kinematics.

Successful, long-term operation of a biofilter system depends on maintaining a suitable biofilm environment within a porous medium reactor. In this article a mathematical study was conducted of the spatial and temporal changes of biofilter performance due to interphase heat and mass transport. The method of volume averaging was used to spatially smooth the three-phase (solid, liquid, and gas) conservation equations over the biofilter domain. The packing medium was assumed to be inert, removing the solid phase mass continuity equation from the system. The finite element method was used to integrate the resulting nonlinear-coupled partial differential equations, tracking eight state variables: temperature, water vapor, dry air, liquid water, biofilm, gas and liquid phase organic pollutant, and nutrient densities, through time and space. A multiphase, gas and liquid flow model was adapted to the biofilter model from previous studies of unsaturated groundwater flow. Newton's method accelerated by an LU direct solver was used to iterate the model for solutions. Effects of packing media on performance were investigated to illustrate the utility of the model. The moisture dynamics and nutrient cycling are presented in Part II of this article. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 73: 282–294, 2001.

The presence of significant denitrification activity in an aerobic toluene-treating biofilter was demonstrated under batch and flow-through conditions. N2O concentrations of 9.2 ppmv were produced by denitrifying bacteria in the presence of 15% acetylene, in a flow-through system with a bulk gas phase O2 concentration of >17%. The carbon source for denitrification was not toluene but a byproduct or metabolite of toluene catabolism. Denitrification conditions were successfully used for the reduction of 60 ppmv nitric oxide to 15 ppmv at a flow rate of 3 L min−1 (EBRT of 3 min) in a fully aerated, 17% v/v O2 (superficially aerobic) biofilter. Higher NO removal efficiency (97%) was obtained by increasing the toluene supply to the biofilter. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 58:408-415, 1998.

The reliability of wastewater reclamation and reuse to meet a given annual risk of infection, considering the variability of enteric virus concentrations, has been investigated. Two concepts related to the reliability and safety of wastewater reclamation and reuse are presented. The first is reliability, defined as the probability that the risk of infection from enteric viruses in reclaimed wastewater does not exceed an acceptable risk. The second is based on the expectation of the acceptable annual risk in which the exposure to enteric viruses may be estimated stochastically by numerical simulation. To assess the potential risks associated with the use of reclaimed wastewater in various reuse applications, four exposure scenarios were tested : golf course irrigation, food crop irrigation, recreational impoundments, and groundwater recharge. Past monitoring data on enteric virus concentrations in unchlorinated secondary effluents in Califomia were used. Because enteric virus concentrations in unchlorinated secondary effluents were found to vary over a wide range, characterizing their variability was found to be extremely important. The reliability criterion of meeting the less than 10 -4 annual risk of infection (less than or equal to one infection per 10 000 population per year) at least 95% of the time was used to assess the safety of using reclaimed wastewater in the four different exposure scenarios. The methodologies used in this study should be refined, based on a larger enteric virus database developed using standardized field and laboratory protocols.

Laboratory and field experiments were conducted using a pilot-scale compost biofilter (approximately 5.7 m 3 /min) to determine the potential of using biofiltration for removing volatile organic compounds (VOCs) from gas streams at publicly owned treatment works. Six compounds commonly found in wastewaters (benzene, trichloromethane, dichloromethane, toluene, tetrachloroethene, and trichloroethene) were selected for quantitative evaluation of removal efficiency. Gas fluxes through the biofilters ranged from 0.3 to 1.8 m 3 /m 2 .min with corresponding pressure drops of 0.1 to 0.7 kPa. Removals of aromatic VOCs averaged greater than 80% during an 8.5-month field study and were typically greater than 90 to 95%, despite highly variable inlet concentrations. Removals of chlorinated VOCs were inconsistent and ranged from none to more than 60%. Low removals of the chlorinated compounds were believed to be due, in part, to the low inlet airstream concentrations, which were generally less than 70 ppb. Removal of H 2 S and odors was excellent throughout the studies, consistent with the findings of other investigators.

Immobilized bacterial cell technology was applied, on a bench scale, to the selective removal of nitrate from contaminated water, together with the segregation of denitrifying bacteria and the carbon energy source from the treated water. The two-chambered reactor, with a microporous membrane for bacterial cell immobilization, performed at an average denitrification rate of 5,800 mg nitrate-nitrogen (NO[sub 3][sup [minus]]-N)/m[sup 2]/d of membrane surface area. A carbon-to-nitrogen mass consumption ratio of 2.2 g organic carbon/gram nitrogen was observed, with a small degree of methanol contamination of the water being treated. A physical model for NO[sub 3][sup [minus]]-N removal based on Fick's law and the measured diffusion coefficient of nitrate through the immobilization structure gave a good correlation with experimental results.

Studies on the life history and host specificity of the knapweed root weevil, Cyphocleonus achates, were made to determine the suitability of this insect as a classical biological control agent for diffuse knapweed (Centaurea diffusa) and spotted knapweed (Centaurea maculosa) in North America. In its natural area of distribution in Europe and western Asia the weevil appears to be restricted to these two knapweeds. Studies on feeding, oviposition and larval development with 71 test plant species revealed that C. achates has indeed a narrow potential host range, restricted to several species in the Centaurea subgenus Acrolophus. Successful development occurred only on C. diffusa, C. maculosa, C. friderici, C. micranthos and C. vallesiaca. C. achates was approved for release into North America on the results of these investigations and the first shipments of beetles were made in 1987. The beetle should be regarded as an important biological control agent of spotted and diffuse knapweed in North America, especially in the warmer and drier parts of the distribution area of the two knapweeds. C. achates is expected to compliment the three species of root-feeding insects already introduced and established in North America in reducing both rosette density and seed production of the two knapweeds. Zusammenfassung Untersuchungen zur Eignung des Russelkafers Cyphocleonus achates Fahr. (Col., Curculionidae) zur biologischen Bekampfung von Centaurea maculosa Lam. und C. diffusa Lam. In der vorliegenden Arbeit werden die Ergebnisse von Untersuchungen zur Biologie und Wirtsspezifi-zitat des Russelkafers Cyphocleonus achates vorgelegt. Ziel dieser Untersuchungen war es, die Eignung dieses Wurzelinsektes fur die klassische biologische Unkrautbekampfung der Sparrigen und der Gefleckten Flockenblume (Centaurea diffusa und C. maculosa) in Nordamerika zu prufen. In seinem naturlichen Verbreitungsgebiet in Europa und Westasien scheint C. achates auf die beiden erwahnten Flockenblumenarten beschrankt zu sein. Die mit 71 Testpflanzenarten durchge-fuhrten Laboruntersuchungen zum Fras- und Eiablageverhalten sowie zur Larvenentwicklung zeigten, das der potentielle Wirtskreis von C. achates eng begrenzt ist, und zwar auf einige Arten der Centaurea Untergattung Acrolophus. Eine vollstandige Entwicklung erfolgte nur auf C. diffusa, C. maculosa, C. friderici, C. micranthos und C. vallesiaca. Basierend auf den in dieser Arbeit vorgestellten Resultaten, wird C. achates fur die Einfuhr und Freilassung nach Nordamerika empfohlen. Es wird erwartet, das der Kafer wesentlich zur biologischen Bekampfung der beiden Flockenblumen beitragen kann. C. achates wurde 1987 fur die Einfuhr nach Nordamerika freigegeben, und die ersten Kafer wurden importiert. Es wird erwartet, das C. achates in allen warmeren und trockeneren Teilen des nordamerikanischen Verbreitungsgebietes von C. diffusa und C. maculosa eingeburgert werden kann und in diesen Gebieten den Effekt der vier bereits eingefuhrten und etablierten Wurzelinsekten auf die Rosettendichte und die Samenproduktion verstarken wird.

Summary: Resume: Zusammenfassung In 1986, the Working Group on Biological Control within the European Weed Research Society planned a weed survey in 10 major crop systems throughout Europe. They were: (1) winter and (2) spring cereals, (3) maize and sorghum, (4) potatoes, (5) sunflower and soya, (6) colza (winter rapeseed), (9) sugar beet and (10) temperate orchards and irrigated Mediterranean orchards. Questionnaires were sent out to prominent weed scientists in all 26 European countries to rate the abundance and frequency of important weeds according to three classes for all crop systems in their respective countries. The results of the survey are presented. Based on the per cent of maximum score attained by individual weed species the 15 most important weeds were determined for each crop, and the 20 top scoring weeds for all crop systems combined. The prospects for biological control of weeds in Europe are discussed. Etude europeenne des mauvaises herbes de dix cultures majeure.s en vue d'identifier les possi-bilites de lutte biologique En 1986, le Groupe de travail sur la lutte biologique au sein de la Societe Europeenne de Mal-herbologie (European Weed Research Society) a organise une enquete sur les mauvaises herbes presentes dans dix cultures majeures d'Europe: (1) cereales d'hiver et (2) d'ete, (3) mais et sorgho, (4) pomme de terre, (5) tournesol et soja, (6) colza, (7) cultures legumieres, (8) vignes et verges mediterraneens non irrigues, (9) bet-terave a sucre et (10) vergers de la zone tem-perees et mediterraneens irrigues. Des questionnaires ont ete envoyes a des mal-herbologues reconnus des 26 pays europeens pour, au moyen d'une classification a trois niveaux, evaluer dans leur pays 1'abondance et la frequence des mauvaises herbes importantes dans ces systemes de culture. Les resultats de 1'enquete sont presentes. Les 15 mauvaises herbes les plus importantes ont ete determinees pourchaque culture en fonc-tion du pourcentage du score maximum atteint par les differentes especes, ainsi que les 20 mauvaises herbes obtenant les plus haul scores pour toutes les cultures combinees. Les possibilites de lutte biologique centre les mauvaises herbes en Europe sont discutees. Erhebung uber die Verbreitung europaischer Unkrautarten als mogliche Zielefiir eine biologis-che Bekampfung in zehn Hattptkultiiren Die Arbeitsgruppe ‘Biologische Bekampfung’ der Europaischen Gesellschaft fur Herbologie plante 1986 eine Unkrautaufnahme in 10 grosen Kulturen in ganz Europa: (1) Wintergetreide. (2) Sommergetreide, (3) Mais und Sorghum, (4) Kartoffel, (5) Sonnenblume und Soja, (6) Winterraps, (7) Gemuse, (8) Wein und nichtbewasserte mediterrane Obstkulturen, (9) Zuckerrube und (10) mitteleuropaische und bewasserte mediterrane Obstkulturen. Das Ergebnis einer Umfrage in allen 26 europaischen Landern uber die Abundanz und Frequenz wichtiger Unkrauter wird dargestellt. Die 15 fur jede Kultur wichtigsten Arten und die 20 allgemein haufigsten Arten wurden bestimmt. Die Moglichkeiten der biologischen Unkrautbekampfung in Europa werden diskutiert.

Experimental and computational studies were completed to assess volatile organic compound (VOC) emissions from wastewater collection systems. Deuterated chloroform solutions were released into two operating collection systems as a VOC tracer. Downstream sampling of the sewer headspace and wastewater was performed and samples were analyzed by mass spectrometry. Results were used to evaluate a two-phase finite volume model for VOC interphase mass transfer and emissions for uniform reaches in sewers. Differences between predicted and experimental average steady-state concentrations were less than 30%, quite adequate for emission estimation purposes given other uncertainties in wastewater characteristics

The first synthesis of benzofuran 2 was achieved in 17% overall yield in seven steps. The key step was a halogen-metal exchange/cyclization reaction. Several examples of this reaction were reported.

The disulfide functionality exists in numerous organic compounds of interest in both chemistry and biology. In view of the fact that the disulfide function is highly susceptible to further oxidation by a broad range of agents, conducting a chemoselective oxidation without further oxidizing the disulfide group poses a synthetic challenge. Disclosed herein are the first examples of such an oxidation in which a series of aldehyde disulfides (la-e) were converted to the corresponding symmetrical carboxylic acid disulfides (2a-e), utilizing sodium chlorite as the oxidant, and dimethyl sulfoxide as both a reaction solvent and an efficient hypochlorous acid scavenger.

Phosphorus loss in runoff from agricultural fields has been identified as an important contributor to eutrophication. The objective of this research was to determine the relationship between phosphorus (P) in runoff from a benchmark soil (Cecil sandy loam; fine, kaolinitic, thermic Typic Kanhapludult) and Mehlich III-, deionized water-, and Fe 2 O 3 -extractable soil P, and degree of phosphorus saturation (DPS). Additionally, the value of including other soil properties in P loss prediction equations was evaluated. Simulated rainfall was applied (75 mm h -1 ) to 54 1-m 2 plots installed on six fields with different soil test phosphorus (STP) levels. Runoff was collected in its entirety for 30 min and analyzed for total P and dissolved reactive phosphorus (DRP). Soil samples were collected from 0- to 2-, 0- to 5-, and 0- to 10-cm depths. The strongest correlation for total P and DRP occurred with DPS (r 2 = 0.72). Normalizing DRP by runoff depth resulted in improved correlation with deionized water-extractable P for the 0- to 10-cm sampling depth (r 2 = 0.81). The STP levels were not different among sampling depths and analysis of the regression equations revealed that soil sampling depth had no effect on the relationship between STP and P in runoff. For all forms of P in runoff and STP measures, the relationship between STP and runoff P was much stronger when the data were split into groups based on the ratio of oxalate-extractable Fe to Al. For all forms of P in runoff and all STP methods, R 2 increased with the inclusion of oxalate-extractable Al and Fe in the regression equation. The results of this study indicate that inclusion of site-specific information about soil Al and Fe content can improve the relationship between STP and runoff P.

Phytophagous insects representing 4 orders, 12 families and 22 species are associated with the roots of Centaurea maculosa Lam. (21 insect species), C. diffusa Lam. (12 insect species) and C. vallesiaca (11 insect species) in Europe. A total of 192 root samples (110 samples of C. maculosa and 41 samples each of C. diffusa and C. vallesiaca) from 71 localities in 8 countries were collected and analysed between 1979 and 1984. Proportions of insect orders in the insect species found on each plant varied considerably between C. maculosa, C. diffusa and C. vallesiaca, but corresponding values for the roots of C. maculosa and C. diffusa showed a concurrent ranking. A total of 30 parasitoid species were reared from these root feeders and parasitisation levels were generally below 10%, but reached up to 45% at two localities. Root feeders (excluding Hemiptera) exploit four distinct root structures on C. maculosa, three on C. diffusa and only two on C. vallesiaca (spatial food niche separation within the plant). Utilization levels of these feeding niches varied greatly between the three host plants. Temporal niche separation does not seem to play a major role in structuring these root feeding insect guilds. Oviposition sites (plants with green leaves) are available throughout the year and larval feeding generally coincides with high levels of water (>60%) and nitrogen (>1.8%) content in the roots (autumn and spring). With regard to species introductions into North America for the biological control of these knapweeds, we suggest that at least one (host specific) species should be selected for each of the different root structures. The potential impact of these root feeders on knapweed population growth and equilibrium density is briefly discussed. Zusammenfassung Zur Entomofauna des Wurzelbereiches der Flockenblumen, Centaurea maculosa Lam., C. diffusa Lam. und C. vallesiaca Jordan in Europa. Raumliche und zeitliche Nischendifferenzierung Phytophage Insekten aus 4 Ordnungen, 12 Familien und 22 Arten bilden die mit den Wurzeln von Centaurea maculosa Lam. (21 Insektenarten), C. diffusa Lam. (12 Insektenarten) und C. vallesiaca Jordan (11 Insektenarten) assoziierte Insektenfauna. Zwischen 1979 und 1984 wurden insgesamt 192 Wurzelproben (110 Proben von C. maculosa und je 41 Proben von C. diffusa und C. vallesiaca) von 71 Lokalitaten aus 8 Landern gesammelt und analysiert. Der relative Anteil bezuglich Insekten-ordnungen aller auf einer Pflanzenart gefundenen Insektenarten schwankte betrachtlich zwischen C. maculosa, C. diffusa und C. vallesiaca, zeigte jedoch eine ubereinstimmende Reihenfolge fur die Wurzelinsekten an C. maculosa und C. diffusa. Insgesamt wurden 30 Parasitoidenarten aus den gesammelten Wurzelphytophagen gezuchtet; der Parasitierungsgrad lag im allgemeinen unter 10%, erreichte jedoch an 2 Lokalitaten 45%. Die Wurzelphytophagen (ohne Hemiptera) nutzen 4 unterschiedliche Wurzelstrukturteile (Gewebe) an C. maculosa, 3 an C. diffusa und nur 2 an C. vallesiaca (raumliche, innerpflanzliche Nischendifferenzierung). Der Nutzungsgrad dieser Frasnischen schwankte betrachtlich zwischen den 3 Wirtspflanzen. Zeitliche Nischendifferenzierung scheint keinen wesentlichen Einflus auf die Strukturierung dieser Wurzelinsektengilden zu haben. Eiablageplatze (Pflanzen mit grunen Blattern) sind uber das ganze Jahr vorhanden, und der Larvenfras fallt im allgemeinen mit hohem Wasser-(>60%) und Stickstoffgehalt (>1,8%) in den Wurzeln zusammen (Herbst und Fruhling). Im Hinblick auf die Einfuhr von Arten zur biologischen Bekampfung dieser Flockenblumen in Nordamerika schlagen wir daher vor, mindestens eine (wirtsspezifische) Art pro Wurzelstrukturteil auszuwahlen. Mogliche Auswirkungen dieser Wurzelphytophagen auf das Wachstum der Flockenblumenpopulationen und deren Gleichgewichtsdichte werden kurz diskutiert.

Immune serum globulin (ISG) prepared by Cohn cold alcohol fractionation of pooled human plasma was reduced with dithiothreitol (DTT) and alkylated with iodoace-tamide and other alkylating agents. Our results show that there are a few labile inter heavy chain disulfide bonds in ISG which react rapidly under mild, non dissociating conditions. The extent of disulfide cleavage is controlled primarily by the ratio of DTT to ISG until about 4–5 disulfide bonds have been reduced. We report detailed studies on the variables of ISG concentration, DTT to ISG ratio, pH, and time, leading to a chemically modified ISG that has a controlled and limited number of reduced and alkylated disulfide bonds.

Das fruher aus Calebassencurare isolierte quartare C-Alkaloid D und das tertiare Caracurin II aus einer sudamerikanischen Strychnos-Art wurden naher untersucht.